Selectivity in Chemiresistive Gas Sensors: Strategies and Challenges

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: April 8, 2025

The demand for highly functional chemical gas sensors has surged due to the increasing awareness of human health monitor metabolic disorders or noncommunicable diseases, safety measures against harmful greenhouse and/or explosive gases, and determination food freshness. Over years dedicated research, several types chemiresistive have been realized with appreciable sensitivities toward various gases. However, critical issues such as poor selectivity sluggish response/recovery speeds continue impede their widespread commercialization. Specifically, mechanisms behind selective response some materials specific analytes remain unclear. In this review, we discuss state-of-the-art strategies employed attain gas-selective materials, particular emphasis on design, surface modification functionalization catalysts, defect engineering, material structure control, integration physical/chemical filtration media. nature surface-gas interactions supporting are elucidated, opening opportunities optimizing fine-tuning sensing performance, guiding selection most appropriate accurate detection This review concludes recommendations future research directions potential further improvements.

Language: Английский

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Quartz-Enhanced Photoacoustic Spectroscopy-Based Acetone and Ammonia Measurements from Human Breath Near 8 μm Wavelength Band

ACS Sensors, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Human breath gas analysis is a noninvasive disease diagnostic approach used to identify different pathological conditions in the human body. Monitoring acetone (C3H6O) and ammonia (NH3) as biomarkers vital diagnosing diabetes mellitus liver disorders, respectively. In this article, quartz-enhanced photoacoustic spectroscopy (QEPAS) technique proposed demonstrated for measuring C3H6O NH3 exhaled samples. We present QEPAS technique-based combined with broadband tunable quantum cascade laser (QCL) operating from 7.9 8.4 μm target both at specific absorption wavelengths. The experimental results show that minimum detection limits (MDLs) of 57 190 ppb were achieved NH3, measured samples collected volunteers. concentration measurements using 8 spectral region agreed blood glucose measurements. measurement limit sensitivity met requirement needed distinguish concentrations obtained healthy person those disorder conditions.

Language: Английский

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Cr-Doped Nanocrystalline TiO2-Cr2O3 Nanocomposites with p-p Heterojunction as a Stable Gas-Sensitive Material

International Journal of Molecular Sciences, Journal Year: 2025, Volume and Issue: 26(2), P. 499 - 499

Published: Jan. 9, 2025

Nanocrystalline TiO2 is a perspective semiconductor gas-sensing material due to its long-term stability of performance, but it limited in application because high electrical resistance. In this paper, nanocomposite with p-p heterojunction introduced based on p-conducting Cr-doped combination Cr2O3. Materials were synthesized via single-step flame spray pyrolysis (FSP) technique and comprehensively studied by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) specific surface area analysis, transition electron microscopy (TEM), energy dispersive (EDX) spectroscopy, photoelectron spectroscopy (XPS), paramagnetic resonance (EPR), Raman spectroscopy. Gas sensor performance direct current (DC) mode was toward number gasses (H2, CO, CH4, NO2, H2S, NH3) as well volatile organic compounds (VOCs) (acetone, methanol, formaldehyde) dry humid conditions. The the obtained materials' gas evaluated alongside an ex situ study structural evolution. High sensitivity oxygenated VOCs lower detection limit below ppm level influence humidity shown. materials connection defect structure doped demonstrated.

Language: Английский

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Recent progress on mass-sensitive gas sensors for environmental and industrial applications

Measurement, Journal Year: 2025, Volume and Issue: unknown, P. 117039 - 117039

Published: Feb. 1, 2025

Language: Английский

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Metastable CoCu₂O₃ Nanocrystals from Combustion‐Aerosols for Molecular Sensing and Catalysis

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 10, 2024

Abstract Metastable nanostructures are kinetically trapped in local energy minima featuring intriguing surface and material properties. To unleash their potential, there is a need for non‐equilibrium processes capable of stabilizing large range crystal phases outside thermodynamic equilibrium conditions by closely flexibly controlling atomic reactant composition, spatial temperature distribution residence time. Here, the capture metastable pseudo‐binary metal oxides at room demonstrated with scalable combustion‐aerosol processes. By combination X‐ray diffraction, electron microscopy on‐line flame characterization, occurrence CoCu 2 O 3 investigated controlled size (4–16 nm) over thermodynamically stable CuO Co 4 . Immediate practical impact exceptional sensing catalytic performance air pollutant detection (e.g., 15 parts‐per‐billion benzene) shown for, least, 21 days. This approach can be extended to various binary, ternary high entropy even more components. Also, secondary loaded on such nanocrystals access novel materials promising actuators, storage or solar cells.

Language: Английский

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Molecularly Imprinted Polymers and Nanocomposites—Essentials Features and Applied Versatilities

Polymer-Plastics Technology and Materials, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 29

Published: Jan. 12, 2025

This manuscript presents a systematic overview of molecularly imprinted polymer-derived nanocomposites, discussing fundamentals, design categorization, and technological worth, according to the reported literature so far. In this concern, nanocomposites polymers have been synthesized with carbonaceous nanoparticles (graphene, carbon nanotube, fullerene) inorganic (metal/metal oxide, metal organic frameworks). Principal synthesis methods applied for consequential include efficient polymerization tactics, like free radical (bulk/emulsion), electropolymerization, sol-gel, precipitation, imprinting approaches (surface or nanoimprinting). Ensuing macromolecular assemblies nanocomposite hybrid depicted valuable characteristics, counting low price, high surface area, functionalities, microstructural variations, structural stability, facile synthesis, desirable porosity, sensitivity toward other molecules depending upon their precision choice processing technique. Subsequently, worth mentioning combinations nanocarbon/inorganic showed scientific potential water remediation (adsorbent materials), gas/electrochemical sensors, drug delivery, biosensing fields. Although plenty reports revealed design, processing, practical aspects polymers; nonetheless, we note, field needs much future attention precise designs, perfect polymer-nanoparticle assemblies, well-defined techniques/parameters commercial-scale utilizations.

Language: Английский

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Outer space H2S detection: CuO-based thin film gas sensors powered by UV-LED in vacuum

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 159681 - 159681

Published: Jan. 1, 2025

Language: Английский

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Development of electrochemical NH3 sensors with large sensitivity depending on the superposition enhancement effect of sensing electrodes

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 160603 - 160603

Published: Feb. 1, 2025

Language: Английский

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3D-printed polymer hollow microneedles on microfluidic platforms for minimally invasive interstitial fluid extraction

Published: Feb. 1, 2025

Language: Английский

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Understanding the role of oxygen interstitials in room temperature acetone sensing by Ga-doped ZnO thin film

Sensors and Actuators B Chemical, Journal Year: 2025, Volume and Issue: 433, P. 137523 - 137523

Published: Feb. 25, 2025

Language: Английский

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